In EP 0,666,018 A, it was proposed to equip a harvesting machine with a device for automatic control of the position of the crop discharging device, which controller is capable of determining the position of a transporting vehicle and positioning the discharging device relative to such vehicle.
In EP 1,151,652 A and EP 1,250,832 A, it was proposed to enter a set-point value for the position of the crop discharging device into a memory device, which memory device is queryable by an input device. The crop discharging device is automatically placed in the position indicated by the retrieved data.
JP 10,000,015 A discloses a thresher wherein a swingable screw conveyor for unloading a grain container is held in a pre-stored position with the aid of sensor-controlled actuators. The number of storable positions of the discharging device is limited, however, and is insufficient for situations in which the relative positions of the harvesting machine and the transporting vehicle change.
DE 198 48 127 A describes a chopper wherein the unloading target distance can be entered via a potentiometer. The unloading target distance can be derived by depressing a pushbutton, based on information about the instantaneous settings of the crop discharging device and specification of the target height. With the aid of a parameter which represents the direction of travel of the chopper, e.g. the steering angle, the crop discharging device is controlled such that the programmed unloading target distance and programmed unloading target height are maintained. When the chopper travels through a curve, the crop discharging device is thus automatically adjusted to unload the harvested material onto the transport vehicle. However, this arrangement can only function if the transport vehicle is traveling on a predefined path, e.g. if the transport vehicle constantly travels behind the chopper or is pulled by the chopper.